Several types of catalytic reaction in two-phase systems are known. One of these is termed phase-transfer catalysis, Dehmlow Angew.Chemie (Eng Ed.) 16,493 (1977) where the reaction takes place in the organic phase by the use of two large organic cations, and where the leaving group enters the aqueous phase. Another system is that of micellar catalysis, Fendler et al, Catalysis in Micellar and macromolecular systems, Academic Press, New York, 1975. The reaction is effected in a micellar system obtained from an organic and an aqueous phase in conjunction with a surface active agent. A highly polar layer is formed at the interphase and this may stabilize the transition state of the reaction. In another system catalytic reactions are effected in a system comprising sulfonated triphenyl phosphine, which serves as catalyst in the aqueous phase, see French patent application No. 2314910.